You play the percentages. Chance of success against a “punt safe” defense (with our “1’s out there) had a very low probably of success, especially in 4th and 11. You call time out at that point and you make a decision on going for with your offense or punt it and play defense. Percentages say punt it and play defense.
Whether Kirby recognized it or not, he basically told his defense one of two things; “we can’t give the ball back with 3 minutes to go. They have the momentum on offense. They’’ll go down, score and win” or “I have faith you guys on defense can stop them on a short field”.
I’m banking on the former as opposed to the latter.
Bottom line is that a fake punt versus a punt safe defense that is completely prepared to stop it (and putting the ball in the hands of a true freshman QB on top of it) was the absolute lowest percentage play to run.